Frostbite
TY 4 Stroke God
I bought one of those Shockwave adjustable helixes for my RX-1M. It's so easy to mess with the engine RPM. It takes less than a minute to change your shift speed.
I was at a mountain airstrip racing and decided to dial up my engine RPM to get more speed out of my sled. Since one factor on gearing charts is engine RPM I gave it a try.
I went from 10,200 to 10,700 and saw I was pulling a bit more top end.
Being charitable and cautious I bumped the RPM up to darn near 11,000 RPM trying to stay just shy of the rev limiter. Once again I saw more top end.
So, why would I want to run at 10,200 when there is more top end to be had by going to a higher operatiing RPM?
Yes, I understand my ETs might not be as high and I may be beyond the max HP of the motor but RPMs equal top end in my limited testing.
For on the trail stuff or even when I'm climbing mountains I can understand wanting to stay at the peak HP (or torque) peak for the engine but for flat out top end speeds it seems RPMs play a major role.
Someone please tell me where I'm missing the boat.
Frosty
I was at a mountain airstrip racing and decided to dial up my engine RPM to get more speed out of my sled. Since one factor on gearing charts is engine RPM I gave it a try.
I went from 10,200 to 10,700 and saw I was pulling a bit more top end.
Being charitable and cautious I bumped the RPM up to darn near 11,000 RPM trying to stay just shy of the rev limiter. Once again I saw more top end.
So, why would I want to run at 10,200 when there is more top end to be had by going to a higher operatiing RPM?
Yes, I understand my ETs might not be as high and I may be beyond the max HP of the motor but RPMs equal top end in my limited testing.
For on the trail stuff or even when I'm climbing mountains I can understand wanting to stay at the peak HP (or torque) peak for the engine but for flat out top end speeds it seems RPMs play a major role.
Someone please tell me where I'm missing the boat.
Frosty
SUPERTUNER
TY 4 Stroke Master
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For racing you will do fine as descibed above. For trail riding you will want to be more into the meat of your torque. Qucker backshifting and all.
Freddie
Freddie
Silver
Expert
I have mine set up to run 10,500 to 10,700 depends on the weather were it runs but for me and my sled that is the best.I did the 98,000 let it creep up to 10,200 the thing was a slug compared to now.I'm sure each sled is a little different some may like more rpm's then others.
Frostbite
TY 4 Stroke God
Thanks guys.
Silver, I too find my sled just LOVES 10,500 to 10,700. That's why I thought I'd try bumping it up to 10,900 and see what happened. It was faster.
Doesn't the REV limiter engage at 11,200? If so, what happens when you hit the REV limiter? Does RPM drop off immediately or does it start to backfire and pop? I honestly don't know.
Frosty
Silver, I too find my sled just LOVES 10,500 to 10,700. That's why I thought I'd try bumping it up to 10,900 and see what happened. It was faster.
Doesn't the REV limiter engage at 11,200? If so, what happens when you hit the REV limiter? Does RPM drop off immediately or does it start to backfire and pop? I honestly don't know.
Frosty
black john
TY 4 Stroke Guru
rev limeter
i under stand that the rev limeter on the rx 1 is at around 10900-11000 rpm but i would think that the valve springs would allso limet the rpm. as when i removed my springs i found that i could take the out with my fingers. and i had a lot of fun putting the H D valve springs back in there place. i to found that the higher the rpm,s went the faster it would go. on those long run,s out on the lake i would see 140 + mph on the dream meter.
i under stand that the rev limeter on the rx 1 is at around 10900-11000 rpm but i would think that the valve springs would allso limet the rpm. as when i removed my springs i found that i could take the out with my fingers. and i had a lot of fun putting the H D valve springs back in there place. i to found that the higher the rpm,s went the faster it would go. on those long run,s out on the lake i would see 140 + mph on the dream meter.
tundra
TY 4 Stroke Junkie
Maybe more top end, but i get better acceleration between 10000 to 10300 rpm. Result am looking for.
